<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>原生JSONP</title>
</head>
<body>
    用户名：<input type="text">
    <p></p>
    <script>
        const Input = document.querySelector('input');
        const p = document.querySelector('p');
        //声明handle
        function handle(data){
            Input.style.border = '1px solid red';
            p.innerHTML = data.message;
        }


        //绑定事件
        Input.onblur = function(){
            //获取用户的输入值
            let username = this.value;
            //向服务端发送请求，检测用户是否存在
            //1.创建script标签
            let script = document.createElement('script');
            //2.设置标签的src属性
            script.src = "http://localhost:8000/user-check-server";
            //3.将script插入到文档中
            document.body.appendChild(script);

        }
    </script>
</body>
</html>